EFFECT OF DIFFERENT SOURCES OF SPECIFIC VARIABILITY ON PRODUCTIVE TRAITS IN SHEEP FROM COPPER-RED SHUMEN BREED

G. Staykova

Abstract: An investigation with 318 sheep from the Copper-Red Shumen breed during the period 2003-2010, originated from Kabiuk herd, Shumen was carried out. Parameters live weight at weaning, 9 months, 1.5 years and 2.5 years of age, wool productivity traits - quantity and wool length at the age of 1,5 years were studied. The information was obtained from the origin books of the breed. All the evaluations and analyses were based on multi-factor linear - statistical models (Harvey, 1990): Y ijklm = μ + A ijklmno + B pqhij + e ijklm. The differences between the levels of the studied factors are established on the base of the arrangement degree, measured by Student (Hayter, A., 1984): yi - yj) / S √( 1/ni + 1/nj) /2. It was established the year of birth was a significant source of specific variability for the traits live weight (Р<0.001), wool yield (Р<0.001)and staple length (Р<0.01) of all studied ages. The breeding line has a significant effect on the wool yield at 1.5 years age (Р<0.05). Effect of the breeding line for the live weight and wool length was not established. The established heritability coefficients of live weight at different age (h2 =0.031, h2 =0.059, h2 =0.315, h2 =0.065), wool yield and wool length at 18 months are low (h2 =0.045 and h2 =0.014), indicate to narrowing of the genetic variety in the population.

Keywords: breeding lines; Copper-Red Shumen sheep; live weight; wool yield; year of birth

Date published: 2017-05-16